Catalina 27 Outboard - 6 or 8 HP?

The Garbone · Jan 30, 2013

ScottGrosenick said:
I have a 1975 C27 whose outboard bit the dust. I'm trying to decide between the Tohatsu 6HP SailPro or 8HP outboard. I'm sure that the 6 would be fine for docking and maneuvering but I'm a little concerned that it wouldn't get the boat to hull speed when motoring for hours in light winds or opposing currents.

People sound like they have liked the one they bought (reviews of both are positive) but I'm not sure which would work better in puget sound and I don't want to load up the transom (which already squats a lot when motoring with my 7.5 two stroke. ...which weighs the same as the 6) without good reason.

Any recommendations on which to choose?

I replaced my 92 Johnson 9.9 long shaft with a 98 Mariner 9.9 long shaft, both 2 strokes. Plan to have the Johnson rebuilt and use it again in a few years when my Mariner wears out.

Both motors will move the boat along a 5knots at about 80% throttle. You can get a 15hp 2stroke and they are the same size and weight as the 9.9s, just cost a bit more.

One thing to consider is the transom hole size. My Mariner rubs just a little, I imagine a new 4stroke would rub.

caguy · Jan 30, 2013

Don't you need a bigger motor for a 7,000# boat in Puget S.?

I was always under the impression that you guys needed to be concerned with tides and currents up there in Puget Sound.
I replaced my inboard 15hp 2 stroke Zephyr motor with an 18hp 2 stroke Tohatsu and am extremely happy with it. I was originally looking for a 15 hp 4 stroke but came across this, use only once, 18hp electric start long shaft real cheap. The 15 and 18's are the same except for the carburetion. It is very quite and dependable. Only stalls when it runs out of gas, go figure. It sits quite well and the boat does not drag because of it. Its like having a small kid (albeit a really fat small kid) on the back of the boat.
It pushes and stops the boat well.

Jon_E · Jan 30, 2013

I had a 15 hp Evinrude 2 stroke long shaft. It fit in the transom cut-out just perfect. Unfortunately, when it ran at the required RPM of 2 strokes it gulped gas, and when I would throttle back it fouled spark plugs over time. When someone made me an attractive offer I sold it.

My next (and current) engine is a 8 hp Yamaha 4 stroke long shaft. It has a high thrust prop and a higher gear ratio which moves the boat just fine in all kinds of conditions. It is very quiet and extremely fuel efficient. The down side is that I had to enlarge the top of the cutout an extra inch so it would fit when retracted. It is also a bit heavier than most 2 strokes.

The Yamaha 9.9 is the same engine with larger carburators. I think the 8 hp model has been discontinued.

For performance and reliability, I cannot say enough about this engine. I would have sworn it was made for a Catalina-27 but for the need to alter the cutout a bit for proper retraction. My C-27 is a 1977 model, and the 2 stroke engines of that time had smaller cowlings than what is available with current 4 stroke models.

There is more to outboards than horsepower. Here is the link to the Yamaha High Thrust models. You'll see these are the types made for sailboats.

http://www.yamahaoutboards.com/outboards/High-Thrust/overview

FYI

centerline · Jan 31, 2013

caguy said:
I was always under the impression that you guys needed to be concerned with tides and currents up there in Puget Sound.

in almost every case, the motor size, provided it will get the boat to hull speed, wont make much difference regarding the tides and currents, due to the theoretical hull speed effect...

when the boat is going at your hull speed of 6kts thru the water, and the water current is running at 8kts, more power wont help...
more motor power will only help when there is a strong head wind or head sea that would otherwise hold you back from making hull speed thru the water... or when your towing another vessel.

FourPoints · Jan 31, 2013

The general guideline is 2hp per 1000lbs of displacement

That will give you enough reserve power to power through chop and current and stormy weather.

for a C27, with a displacement of 6800lbs, you should go with a 15hp

Chris Patterson · Jan 31, 2013

If you put a 6 on that boat, you will be very discouraged quickly. And probably the eight as well. NO smaller than 9.9

foolproof · Jan 31, 2013

I had a 9.9 on my old Catalina 25 and was not very happy with its performance. I always thought that I was underpowered. Go with a 15 horse...it will have the power to get you to hull speed and run at that speed without a lot of effort.

caguy · Feb 2, 2013

ScottGrosenick said:
I'm not sure why folks are recommending such beefy motors - I easily maintained hull speed (not through 6 foot rollers but I wouldn't expect to) with my 1978 7.5hp.

If you aren't happy with a 6 or an 8 on a C27 (or smaller) - what expectations weren't met? Sure, I wouldn't expect to get it up on a plane but I can't see how 15hp would be anything but overkill.

In my case it is the size of the inboard motor hp that came with the boat. Going out to Catalina you never know when you may run into a 6-8 ft roller.

Jon_E · Feb 4, 2013

ScottGrosenick said:
I'm not sure why folks are recommending such beefy motors - I easily maintained hull speed (not through 6 foot rollers but I wouldn't expect to) with my 1978 7.5hp.

If you aren't happy with a 6 or an 8 on a C27 (or smaller) - what expectations weren't met? Sure, I wouldn't expect to get it up on a plane but I can't see how 15hp would be anything but overkill.

Thank you! I feel rather lonely here being the only guy happy with my 8 hp high thrust outboard. I never run in full out. I have made several trips to Catalina (about 30 miles) and never have come close to draining the 6 gallon tank since switching from the 15 hp.

I think a 15 hp would be needed if the propeller was not the right type.

caguy · Feb 4, 2013

Took some pictures on Saturday of the Tohatsu 18 on the Cat 27. The other thing to consider is the electric start and remote controls. For me it is a must have especially on the C-27. Controls on motor are not easily reachable.

Elysium_Van_Isl · Feb 4, 2013

The BEST thing I ever did on my 27 was to buy a Yamaha 8high thrust. We cruise along at 3/4 throttle and about 6kts. Fuel economy is great. Only problem is that it's a Verrrry tight fit on the back. The lazarette lid doesn't close 100% when I tilt the engine up. Just never thought that was a big deal.
Quick story- I actually used that engine to tow a friend's Cat. 30 from Barkley Sound on the West Coast, all the way down to Victoria. It didn't skip a beat.

sdfox · Feb 5, 2013

Yamaha 9.9HT

Jon_E said:
Thank you! I feel rather lonely here being the only guy happy with my 8 hp high thrust outboard. I never run in full out. I have made several trips to Catalina (about 30 miles) and never have come close to draining the 6 gallon tank since switching from the 15 hp.

I think a 15 hp would be needed if the propeller was not the right type.

You're not alone. I got rid of my 86 Johnson 8 and bought the Yami 9.9 4strk high thrust WITH the controls and electric start. No more diving into the aft compartment to shift, throttle, start, stop, etc. The yamaha runs so blasted quiet that I've had to look over the side to see the telltale stream to make sure its running. It's very easy on gas (we have 2 6gal tanks, use about 10g during "summer" in Duluth, MN) and I've only run it up to 3/4 throttle in a 28k headwind and maintained 5k. Normal for us is 1/2 at 5.5k. You're right about the opening being tight (we have a 79 cat 27). I haven't enlarged it yet so that I can tilt clear of the water. Also had to place a stop/resting block so that the lower unit doesn't tilt all the way down and interfere with the rudder. The PO had notched the rudder and I repaired the notch before getting the Yamaha.

Bad news is the admiral has taken over the helm and I no longer get to "drive" the boat. She does all of the into and out of the dock and sailing. I get to rig, hoist, haul and trim sails.

scotty

The Garbone · Feb 5, 2013

Re: Yamaha 9.9HT

For working my throttle I bought a 14" tiller extension on Amazon for $15. Drilled a hole in my hatch. Works pretty well.

Patrice · Feb 7, 2013

Hi,
I had a mercury 6HP, 2 strokes on my previous C-25. And it was not enough for safety.
Yes I was able to make hull speed without full trottle. The issue was when wind would pick up, and waves. Then it wasn't powerfull enough, had issue coming back to the slip, or making it to the protected bay easily.
And a C-25 is not as heavy.
If you're going to buy, buy enough to feel safe.
My opinion.

Jon_E · Feb 18, 2013

Here is an interesting article in Sail magazine. Two vastly different sized boats with the same horsepower engine. It's all about "propellers and shaft speeds."

http://www.sailmagazine.com/boatworks/fuel-consumption-tug-vs-cruiser